code: def test_for_strings():
      strings = getmembers(ray, lambda obj: isinstance(obj, str))
      for string, _ in strings:
          assert string.startswith(
              "__"
          ), f"Invalid string: {string} found in "
          "top level Ray. Please delete at the end of __init__.py."
  
file_path: ray/python/ray/tests/test_top_level_api.py
imports: from inspect import getmembers, isfunction, ismodule
  import sys
  import pytest
  import ray
label_desc: Use image node_id 6 for calling a global function with example usage: test_for_strings() without return types